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1.
Curr Microbiol ; 81(8): 229, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896154

RESUMEN

Standing dead trees (snags) are recognized for their influence on methane (CH4) cycling in coastal wetlands, yet the biogeochemical processes that control the magnitude and direction of fluxes across the snag-atmosphere interface are not fully elucidated. Herein, we analyzed microbial communities and fluxes at one height from ten snags in a ghost forest wetland. Snag-atmosphere CH4 fluxes were highly variable (- 0.11-0.51 mg CH4 m-2 h-1). CH4 production was measured in three out of ten snags; whereas, CH4 consumption was measured in two out of ten snags. Potential CH4 production and oxidation in one core from each snag was assayed in vitro. A single core produced CH4 under anoxic and oxic conditions, at measured rates of 0.7 and 0.6 ng CH4 g-1 h-1, respectively. Four cores oxidized CH4 under oxic conditions, with an average rate of - 1.13 ± 0.31 ng CH4 g-1 h-1. Illumina sequencing of the V3/V4 region of the 16S rRNA gene sequence revealed diverse microbial communities and indicated oxidative decomposition of deadwood. Methanogens were present in 20% of the snags, with a mean relative abundance of < 0.0001%. Methanotrophs were identified in all snags, with a mean relative abundance of 2% and represented the sole CH4-cycling communities in 80% of the snags. These data indicate potential for microbial attenuation of CH4 emissions across the snag-atmosphere interface in ghost forests. A better understanding of the environmental drivers of snag-associated microbial communities is necessary to forecast the response of CH4 cycling in coastal ghost forest wetlands to a shifting coastal landscape.


Asunto(s)
Bacterias , Bosques , Metano , Microbiota , ARN Ribosómico 16S , Humedales , Metano/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , ARN Ribosómico 16S/genética , Árboles/microbiología , Filogenia , Oxidación-Reducción , Archaea/clasificación , Archaea/genética , Archaea/metabolismo , Aerobiosis
2.
Cell Metab ; 35(4): 695-710.e6, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36963395

RESUMEN

Associations between human genetic variation and clinical phenotypes have become a foundation of biomedical research. Most repositories of these data seek to be disease-agnostic and therefore lack disease-focused views. The Type 2 Diabetes Knowledge Portal (T2DKP) is a public resource of genetic datasets and genomic annotations dedicated to type 2 diabetes (T2D) and related traits. Here, we seek to make the T2DKP more accessible to prospective users and more useful to existing users. First, we evaluate the T2DKP's comprehensiveness by comparing its datasets with those of other repositories. Second, we describe how researchers unfamiliar with human genetic data can begin using and correctly interpreting them via the T2DKP. Third, we describe how existing users can extend their current workflows to use the full suite of tools offered by the T2DKP. We finally discuss the lessons offered by the T2DKP toward the goal of democratizing access to complex disease genetic results.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/genética , Acceso a la Información , Estudios Prospectivos , Genómica/métodos , Fenotipo
3.
J Exp Bot ; 72(12): 4489-4501, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-33677600

RESUMEN

The influence of aquaporin (AQP) activity on plant water movement remains unclear, especially in plants subject to unfavorable conditions. We applied a multitiered approach at a range of plant scales to (i) characterize the resistances controlling water transport under drought, flooding, and flooding plus salinity conditions; (ii) quantify the respective effects of AQP activity and xylem structure on root (Kroot), stem (Kstem), and leaf (Kleaf) conductances; and (iii) evaluate the impact of AQP-regulated transport capacity on gas exchange. We found that drought, flooding, and flooding plus salinity reduced Kroot and root AQP activity in Pinus taeda, whereas Kroot of the flood-tolerant Taxodium distichum did not decline under flooding. The extent of the AQP control of transport efficiency varied among organs and species, ranging from 35-55% in Kroot to 10-30% in Kstem and Kleaf. In response to treatments, AQP-mediated inhibition of Kroot rather than changes in xylem acclimation controlled the fluctuations in Kroot. The reduction in stomatal conductance and its sensitivity to vapor pressure deficit were direct responses to decreased whole-plant conductance triggered by lower Kroot and larger resistance belowground. Our results provide new mechanistic and functional insights on plant hydraulics that are essential to quantifying the influences of future stress on ecosystem function.


Asunto(s)
Acuaporinas , Sequías , Ecosistema , Inundaciones , Hojas de la Planta/metabolismo , Transpiración de Plantas , Salinidad , Agua/metabolismo
4.
J Med Imaging Radiat Sci ; 49(1): 97-105, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-30479296

RESUMEN

OBJECTIVE: The project aims were: (1) identifying the pedagogical impact of collaborative student experience on student understanding of research methods and (2) evaluating the perceived value of providing students with an international perspective on their professional practice. METHODS: Student cohorts from year 1 of the University of Liverpool (UoL) (n = 80) and year 2 of the Royal Melbourne Institute of Technology University (RMIT) (n = 128) undergraduate Medical Radiation Science degree programmes participated in the intervention as part of their teaching. Students were tasked with designing, deploying, and analysing data from survey-based research projects and invited to provide feedback via an anonymous and voluntary online survey (UoL students) or an equivalent paper-based survey (RMIT students), comprising both quantitative (Likert) and qualitative (open) questions. RESULTS: Responses were received from 83% of RMIT and 31% of UoL students. Over 42% of respondents enjoyed the opportunity to interact with overseas peers, while 14.7% did not; 40% of respondents felt the intervention helped in their understanding of research methods, whilst 28% indicated it had not. The main positive themes were learning the research process, team working skills, networking opportunities, and understanding cultural differences. Interpreting data were invaluable; only a minority valued the engagement with their overseas counterparts. There was poor engagement with social media. CONCLUSIONS: Students reported clear value of the innovation for learning research skills and process. The extent of research skills learning supports changes in research activity and culture in the past 10 years. With internationalisation becoming increasingly important in today's health care economy, the degree to which the students identified this aspect of the research as a key learning point highlights the benefits of the active approach. The negative appraisal of the social media support was interpreted as a response to the platform (WhatsApp) and privacy issues with sharing phone numbers.


Asunto(s)
Investigación Biomédica/educación , Educación de Pregrado en Medicina/métodos , Oncología por Radiación/educación , Curriculum , Personal de Salud , Humanos , Internacionalidad , Práctica Profesional , Medios de Comunicación Sociales
5.
CBE Life Sci Educ ; 15(3)2016.
Artículo en Inglés | MEDLINE | ID: mdl-27543637

RESUMEN

Xavier University of Louisiana leads the nation in awarding BS degrees in the biological sciences to African-American students. In this multiyear study with ∼5500 participants, data-driven interventions were adopted to improve student academic performance in a freshman-level general biology course. The three hour-long exams were common and administered concurrently to all students. New exam questions were developed using Bloom's taxonomy, and exam results were analyzed statistically with validated assessment tools. All but the comprehensive final exam were returned to students for self-evaluation and remediation. Among other approaches, course rigor was monitored by using an identical set of 60 questions on the final exam across 10 semesters. Analysis of the identical sets of 60 final exam questions revealed that overall averages increased from 72.9% (2010) to 83.5% (2015). Regression analysis demonstrated a statistically significant correlation between high-risk students and their averages on the 60 questions. Additional analysis demonstrated statistically significant improvements for at least one letter grade from midterm to final and a 20% increase in the course pass rates over time, also for the high-risk population. These results support the hypothesis that our data-driven interventions and assessment techniques are successful in improving student retention, particularly for our academically at-risk students.


Asunto(s)
Biología/educación , Evaluación Educacional/métodos , Grupos Minoritarios/educación , Modelos Educacionales , Estudiantes , Curriculum , Minería de Datos , Femenino , Humanos , Masculino , Análisis de Regresión , Riesgo
6.
Environ Microbiol Rep ; 7(4): 592-605, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25865809

RESUMEN

Little is known about the fungal role in biogeochemical cycling in oligotrophic ecosystems. This study compared fungal communities and assessed the role of exogenous carbon on microbial community structure and function in two southern Appalachian caves: an anthropogenically impacted cave and a near-pristine cave. Due to carbon input from shallow soils, the anthropogenically impacted cave had an order of magnitude greater fungal and bacterial quantitative-polymerase chain reaction (qPCR) gene copy numbers, had significantly greater community diversity, and was dominated by ascomycotal phylotypes common in early phase, labile organic matter decomposition. Fungal assemblages in the near-pristine cave samples were dominated by Basidiomycota typically found in deeper soils (and/or in late phase, recalcitrant organic matter decomposition), suggesting more oligotrophic conditions. In situ carbon and manganese (II) [Mn(II)] addition over 10 weeks resulted in growth of fungal mycelia followed by increased Mn(II) oxidation. A before/after comparison of the fungal communities indicated that this enrichment increased the quantity of fungal and bacterial cells, yet decreased overall fungal diversity. Anthropogenic carbon sources can therefore dramatically influence the diversity and quantity of fungi, impact microbial community function, and stimulate Mn(II) oxidation, resulting in a cascade of changes that can strongly influence nutrient and trace element biogeochemical cycles in karst aquifers.


Asunto(s)
Biota/efectos de los fármacos , Carbono/metabolismo , Cuevas , Hongos/clasificación , Manganeso/metabolismo , Microbiología del Suelo , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Carga Bacteriana , Basidiomycota , Recuento de Colonia Microbiana , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Alimentos , Hongos/genética , Hongos/crecimiento & desarrollo , Hongos/metabolismo , Datos de Secuencia Molecular , Micelio/crecimiento & desarrollo , Oxidación-Reducción , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
7.
J Med Radiat Sci ; 62(4): 253-60, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27512571

RESUMEN

INTRODUCTION: This article presents the results of a single-day census of radiation therapy (RT) treatment and technology use in Australia. The primary aim of the study was to ascertain patterns of RT practice and technology in use across Australia. These data were primarily collated to inform curriculum development of academic programs, thereby ensuring that training is matched to workforce patterns of practice. METHODS: The study design was a census method with all 59 RT centres in Australia being invited to provide quantitative summary data relating to patient case mix and technology use on a randomly selected but common date. Anonymous and demographic-free data were analysed using descriptive statistics. RESULTS: Overall data were provided across all six Australian States by 29 centres of a possible 59, yielding a response rate of 49% and representing a total of 2743 patients. Findings from this study indicate the increasing use of emerging intensity-modulated radiotherapy (IMRT), image fusion and image-guided radiation therapy (IGRT) technology in Australian RT planning and delivery phases. IMRT in particular was used for 37% of patients, indicating a high uptake of the technology in Australia when compared to other published data. The results also highlight the resource-intensive nature of benign tumour radiotherapy. CONCLUSIONS: In the absence of routine national data collection, the single-day census method offers a relatively convenient means of measuring and tracking RT resource utilisation. Wider use of this tool has the potential to not only track trends in technology implementation but also inform evidence-based guidelines for referral and resource planning.


Asunto(s)
Pautas de la Práctica en Medicina/estadística & datos numéricos , Garantía de la Calidad de Atención de Salud , Equipos y Suministros de Radiación/estadística & datos numéricos , Radioterapia/estadística & datos numéricos , Australia , Instituciones de Salud/estadística & datos numéricos , Humanos , Equipos y Suministros de Radiación/provisión & distribución , Radioterapia/instrumentación , Radioterapia/normas
8.
J Med Radiat Sci ; 61(1): 45-50, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26229635

RESUMEN

INTRODUCTION: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students' experience on clinical placement. METHODS: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanisms during clinical placements in a semester. RESULTS: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. CONCLUSIONS: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning.

9.
J Med Radiat Sci ; 61(4): 241-245, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25598977

RESUMEN

INTRODUCTION: The multifactorial nature of clinical skills development makes assessment of undergraduate radiation therapist competence level by clinical mentors challenging. A recent overhaul of the clinical assessment strategy at Queensland University of Technology has moved away from the high-stakes Objective Structured Clinical Examination (OSCE) to encompass a more continuous measure of competence. This quantitative study aimed to gather stakeholder evidence to inform development of standards by which to measure student competence for a range of levels of progression. METHODS: A simple anonymous questionnaire was distributed to all Queensland radiation therapists. The tool asked respondents to assign different levels of competency with a range of clinical tasks to different levels of student. All data were anonymous and was combined for analysis using Microsoft Excel. RESULTS: Feedback indicated good agreement with tasks that specified the amount of direction required and this has been incorporated into the new clinical achievements record that the students need to have signed off. Additional puzzling findings suggested higher expectations with planning tasks than with treatment-based tasks. CONCLUSION: The findings suggest that the amount of direction required by students is a valid indicator of their level and has been adopted into the clinical assessment scheme. Further work will build on this to further define standards of competency for undergraduates.

11.
J Med Radiat Sci ; 60(1): 25-34, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26229604

RESUMEN

INTRODUCTION: Undergraduate students studying the Bachelor of Radiation Therapy at Queensland University of Technology (QUT) attend clinical placements in a number of department sites across Queensland. To ensure that the curriculum prepares students for the most common treatments and current techniques in use in these departments, a curriculum matching exercise was performed. METHODS: A cross-sectional census was performed on a pre-determined "Snapshot" date in 2012. This was undertaken by the clinical education staff in each department who used a standardized proforma to count the number of patients as well as prescription, equipment, and technique data for a list of tumour site categories. This information was combined into aggregate anonymized data. RESULTS: All 12 Queensland radiation therapy clinical sites participated in the Snapshot data collection exercise to produce a comprehensive overview of clinical practice on the chosen day. A total of 59 different tumour sites were treated on the chosen day and as expected the most common treatment sites were prostate and breast, comprising 46% of patients treated. Data analysis also indicated that intensity-modulated radiotherapy (IMRT) use is relatively high with 19.6% of patients receiving IMRT treatment on the chosen day. Both IMRT and image-guided radiotherapy (IGRT) indications matched recommendations from the evidence. CONCLUSION: The Snapshot method proved to be a feasible and efficient method of gathering useful data to inform curriculum matching. Frequency of IMRT use in Queensland matches or possibly exceeds that indicated in the literature. It is recommended that future repetition of the study be undertaken in order to monitor trends in referral patterns and new technology implementation.

15.
Newsweek ; 152(22): 8, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-19058746
16.
Newsweek ; 152(22): 13, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-19058747
19.
Newsweek ; 151(23): 15, 2008 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-18822595
20.
Newsweek ; 151(23): 54, 2008 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-18822597
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